bus rapid transit BRT is a bus system where the buses travel in a dedicated lane in the center of the roadway. The buses are more efficient and on time because they do not mix with the car traffic.

BRT basics
dedicated right-of-way; bus-only lanes
bus-only corridor; bus has own lane in the center of the roadway
off-board fare collection; no waiting to pay on board 
intersection treatments; no traffic across the bus lane 
platform-level boarding; easier, accessible for wheelchairs, strollers, carts 
what does the platform look like?

the platform is in the centerline, where everything is at the right height so passengers step from the platform level to the bus.

bus rapid transit
bus rapid transit BRT in Bogata, Columbia